Clamping tools have been suggested for the purpose of supporting sections of pipe, I-beams or the like to be welded, in which the clamping members are mounted on a self-locking C-clamp. Examples of such prior devices include the patents of Stockmar U.S. Pat. No. 57,447 of Aug. 21, 1866; Bardes, U.S. Pat. No. 4,305,575 of Dec. 15, 1981; Bardes, U.S. Pat. No. 4,238,123 of Dec. 9, 1980; Holmes, U.S. Pat. No. 4,327,902 of May 4, 1982; Dearman, U.S. Pat. No. 4,378,937 of Apr. 5, 1983; and Dearman, U.S. Pat. No. 4,483,059 of Nov. 20, 1984.
In the prior devices noted, each arm or jaw of a locking tool is provided with a workpiece gripping member which is pivotally or movably mounted with respect to the arm, to permit the gripping member to have a certain degree of alignment or movement with respect to a workpiece being clamped. While the arrangements as shown and described in the above identified prior patents are useful for supporting a variety of different articles, each lacks an ability to hold and support a wide variety of workpieces of substantially differing shapes or configurations. In fact, with the possible exception of Stockmar, each is particularly designed for the purpose of supporting workpieces of specific or limited configurations. Further, the prior devices shown generally lack the ability to support simultaneously, two or more articles of substantially differing configurations, such as cylindrical pipe and flat plates, beams, or rectangular plates. Also, they lack the versatility of holding, for example, pipes of differing sizes, I-beams, channel beams, flat stock, rod stock, either singly or in combination with other pieces. Accordingly, a need exists for a more univeral and versatile clamping tool.